This invention relates to propynyl uracils and the use of such compounds as biocides.
Ureas and uracils are known to be effective as herbicides and plant growth regulators. See, for example, U.S. Pat. Nos. 5,127,935; 5,354,730; and 5,356,863.
Although there are numerous uracil herbicidal compositions on the market, there is a continuing need for neutral compositions with high biocidal efficacy.
Krivonogov, V. P. et al., Zh. Prikl. Khim., 70(2):315-320 (1997), describe the use of 6-methyl-1,3-di-2-propynyl-2,4(1H, 3H)-pyrimidinedione in the alkylation of 6-methyluracil and derivatives thereof.
Kundu, Nitya G. et al., J. Pharm. Sci., 71(8):935-8 (1982), disclose the preparation of 1,3-dipropargyl-5-fluorouracil and its use in the preparation of N-alkylated derivatives of 5-fluorouracil.
Applicants have discovered propynyl uracils having high biocidal activity and methods of preparing such compounds. These compounds are useful as biocides, such as bactericides, fungicides, and preservatives.
Biocidal compositions comprising a microbiocidally effective amount of one or more of the propynyl uracils of the present invention are a further embodiment of the present invention.
Still another embodiment is a method of controlling microorganisms comprising applying a microbiocidally effective amount of one or more propynyl uracils to the microorganisms.
The present invention encompasses propynyl uracils having formula I below: 
where R1 is hydrogen, chlorine, bromine, iodine, fluorine, xe2x80x94CN, substituted or unsubstituted linear or branched C1-C4 alkyl, xe2x80x94NO2, methoxy, ethoxy, n-propoxy, or iso-propoxy; R2 is iodine or bromine; and R3 is propynyl, 3-iodopropynyl, 3-bromopropynyl, substituted or unsubstituted 2-furanyl, substituted or unsubstituted 3-furanyl, substituted or unsubstituted 2-pyrrolidinyl, substituted or unsubstituted 3-pyrrolidinyl, D-ribose, or deoxyribose. R1 is preferably hydrogen, methyl, chlorine, bromine, fluorine, or iodine and more preferably chlorine or bromine. R3 is preferably 3-iodopropynyl or 3-bromopropynyl.
Examples of compounds of formula I include, but are not limited to, 1N,3N-bis(3-iodo-2-propynyl)-5-chlorouracil; 1N,3N-bis(3-iodo-2-propynyl)-uracil; 1N,3N-bis(3-iodo-2-propynyl)-5-methyluracil; 1N-(3-iodo-2-propynyl)-3N-(2-furanyl)-5-fluorouracil; 1N,3N-bis(3-iodo-2-propynyl)-5-bromouracil; and 1N,3N-bis(3-bromo-2-propynyl)-5-bromouracil. Examples of more preferred compounds of formula I include, but are not limited to, 1N,3N-bis(3-iodo-2-propynyl)-5-chlorouracil and 1N,3N-bis(3-iodo-2-propynyl)-uracil.
Another embodiment of the invention encompasses propynyl uracils having formula II below: 
where R4 is hydrogen, chlorine, bromine, iodine, fluorine, xe2x80x94CN, substituted or unsubstituted linear or branched C1-C4 alkyl, xe2x80x94NO2, methoxy, ethoxy, n-propoxy, or iso-propoxy; R5 is hydrogen or propynyl; and R6 is iodine or bromine. Preferably, R6 is iodine. An example of a compound of formula II is 3N-(3-iodo-2-propynyl)-5-nitrouracil.
The invention further includes a biocidal (or fungicidal) concentrate comprising from about 1 to about 15%, preferably from about 1 to about 5%, by weight of one or more propynyl uracils of the present invention based upon 100% weight of total concentrate. Biocides are materials that prevent the growth of, inhibit the growth of, or kill microorganisms, including, but not limited to, bacteria and fungi.
Generally, the concentrate further comprises from about 1 to about 10%, preferably from about 1 to about 5%, by weight of a solid or liquid formulation adjuvant and up to 15%, preferably from about 0.5 to 10%, by weight of one or more surfactants, based upon 100% weight of total concentrate.
The compositions may also comprise further auxiliaries, such as wetting agents, adhesives, emulsifiers, preservatives, fillers, carriers, viscosity and pH regulators, binders, tackifiers, fertilizers, and other active ingredients. Other conventional adjuvants may be added to the compositions for different applications as known to those of ordinary skill in the art.
The propynyl uracils may be incorporated into different formulations including, but not limited to, granules, pellets, tablets, wettable powders, wettable dusts, microencapsulated materials, impregnated materials, emulsifiable concentrates, flowable concentrates, soluble concentrates, and ready-to-use solutions. The concentrates, granules, pellets, tablets, dusts, and other materials may be diluted with a solvent, such as water, to form a use dilution of the propynyl uracils which may be used as a biocide, such as a bactericide, fungicide, herbicide, or preservative. The use dilution comprises a microbiocidally, bactericidally, or fungicidally effective amount of one or more propynyl uracils of the present invention. Generally, the use dilution comprises from about 0.0005 to about 5% and preferably from about 0.001 to about 0.1% by weight of the propynyl uracils based upon 100% of total use dilution.
Examples of compositions which may contain the propynyl uracils of the present invention include, but are not limited to, personal care products, such as shampoos; wood treatment products; paper products; water treatment equipment; and the like.
Also, the invention includes a method of controlling microorganisms, including bacteria and fungi, comprising applying a microbiocidally, bactericidally, or fungicidally effective amount of one or more of the propynyl uracils of the present invention to the microorganisms.
The propynyl uracils of formula I above may be prepared by reacting a uracil having formula III below: 
where R1 and R3 are defined as in formula I with dimethyl formamide, potassium carbonate, and iodopropargyl 4-methylbenzenesulfonate or bromopropargyl 4-methylbenzenesulfonate. Iodopropargyl 4-methylbenzenesulfonate may be prepared as described in European Patent No. EP 539,114-A2.
Alternatively, the propynyl uracils of formula I may be prepared by reacting a uracil of formula III with sodium iodide, dimethyl formamide, potassium carbonate, and propargyl bromide to produce the corresponding 1N-propynyl uracil. The 1N-propynyl uracil is then iodinated or brominated by reacting it with N-iodosuccinimide or N-bromosuccinimide in the presence of silver nitrate to yield the desired propynyl uracil of formula I.
The propynyl uracils of formula II above, where R5 is propynyl, may be prepared by reacting a uracil having the formula 
where R4 and R6 are defined as in formula II with sodium iodide, dimethyl formamide, potassium carbonate, and propargyl bromide.
The propynyl uracils of formula II, where R5 is hydrogen, may be prepared by reacting a uracil having the formula 
where R4 is defined as in formula II with anhydrous dimethylformamide, potassium t-butoxide, and iodopropargyl-4-methyl-benzene sulfonate or bromopropargyl-4-methyl-benzene sulfonate.
Mixing, adding, and reacting steps in the present invention can be accomplished by conventional means known to those of ordinary skill in the art. The order of addition of reactants or solvent does not affect the process. Reactants and/or solvent can be added sequentially or simultaneously in any suitable reaction vessel. Importantly, the method of the present invention is suitable for commercial scale production techniques and equipment, yet convenient for small scale work.